Sign In | Sign Up | Help | Invite    
Advanced Search Ask A Question Community Recent Changes
My:             Contributions   
Contributors
{for ul in pageInfo.page}
${ul.nickName}
{var al = toBreakWord(ul.adUrl,18)} {if ul.adSentence !=''}${ul.adSentence}
{/if} {if ul.adUrl !=''}${al}
{/if}
 
{/for}
Earn Free Advertising   +   Earn Money By Writing What You Know at WISTEME.COM
Question Discussion History

Edit
    Question ID:   14065         Current Version: 1
Question: What is the surface temperature of a white dwarf star?
Category: Science > Astronomy & Space
Keywords: surface temperature, white dwarf star
Type: what
Rating:(0 ratings)    Views: 206    Discussions: 0   In Watch Lists: 1  

 
    Answer:
As you may know, a white dwarf is the cinder of a star which used to be like the Sun. At the end of its life, such a star expels much of its atmosphere, and the nuclear fusion stops. The hot core, about the size of the Earth but much denser, becomes exposed: this is the white dwarf.

When a star has just become a white dwarf, it is hotter than 100,000 °K (about 180,000 °F). It then gradually cools --- after many billions of years, it can become cooler than the Sun (which is about 6,000 °K). So there is no particular temperature associated with the white dwarfs.

They are called 'white dwarfs', but not all are actually white; the first few that were discovered are white, with temperatures near 10,000 °K. These are still the easiest to discover, so perhaps you can say that 10,000 °K is the typical temperature of white dwarfs that we know of.

Blue (say 50,000 °K) 'white dwarfs' are rare because they cool quickly; yellow and red (cooler than, say 6,000 °K) ones are dim and very hard to discover, but there may be many if we look hard enough. Some astronomers look for these cool white dwarfs and estimate how long they have been cooling, so they can say something about the age of the Universe.

Source: NASA
Read more questions from WISTEME through
     Add to MSN Add to My AOL
 Rate this Question
   Add to Groups   Add to Watch Lists   Share Question
                          
 
    More Readings :
[QID:13929]    What is a white dwarf?  
[QID:13930]    What's inside a white dwarf?  
[QID:6612]    What is sea surface temperature (SST)?  
[QID:1349]    What is "El Nino" and what are its effects?  
[QID:13110]    How does sea surface temperatures affect corals?  
[QID:4048]    What is La Nina and what are its impacts?  
[QID:13445]    What happens when galaxies collide?  
[QID:10092]    What are the seasons of the sun?  
[QID:9440]    What is Dark Energy?  
[QID:6884]    Who was the first woman to travel in space?  
     Question ID:  ${question.id}         Current Version:  ${question.version}

{for qh in questionHistory} {if qh.status == 'r'} {else} {/if} {/for}
Version Contributor Date (ET) Voting
${qh.version} ${qh.nickName} ${qh.date} Rejected
${qh.version} ${qh.nickName} ${qh.date} {if qh.status != 'c'} {if qh.status == 'a'} Approved {else} {if qh.rstatus == 'c'} On-going {else} Pending {/if} {/if} {else}   {/if}
Start a New Topic
ID Topics Replies Latest Post (ET)
{if dlist!=null} {for d in dlist} {/for}
${parseInt(d_index)+1} ${d.sentence} ${d.replyNum} ${d.lastestDate}
{else}
No discussion topic.
{/if}
Label Name:
 
Group Name:
 
 
{else}
     You have no group.
{/if}
Advertisements
{if advertisements.length > 0} {else} {/if}
{for ad in advertisements}
${ad.adTitle}
${ad.adSentence}
${ad.adUrl}
{/for}

Home | About Us | Terms of Use | Privacy Policy | Browse Questions | RSS Feed

Copyright ©2010 WISTEME LLC. All Rights Reserved.